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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 823-839页

作者： kai-ming yang Yong-jiang GUO School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-class reentrant line under first-buffer first-served(FBFS)service discipline in light traffic,we firstly construct the strong approximations for performance measures including the queue length,workload,busy time and idle time *** on the obtained strong approximations,we use a strong approximation method to find all the law of the iterated logarithms(LILs)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival and service times,and characterize the fluctuations around their fluid approximations.

关键词： reentrant line queueing network FBFS service discipline strong approximation LIL Brownian motion

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： Jian CAO Yong-jiang GUO kai-ming yang School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

ISLET FORMATION AND REGENERATION

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Chinese Medical Sciences Journal 2006年第1期21卷 27-32页

作者： kai-ming yang Ai-dong Li Yan Mei Hong-ying Zhou Hua Li Hui-jun yang Department of Anatomy West China Center of Medical Sciences Sichuan University Chengdu 610041 Chengdu Medical College Chengdu 610083

Objective To explore the mechanisms of differentiation and development of pancreatic endocrine cells as well as pancreatic *** Human embryonic pancreatic tissue at 7-14 weeks of gestation was *** mellitus rat model was induced with 65 mg/kg of ***, glucagon, somatostatin, nestin, and cytokeratin 19 (CK19) of pancreatic tissues were observed by *** At 9 weeks of gestation, pancreatic epithelial cells began to co-express insulin, glucagon, somatostatin, and CK19 before *** cells gradually congregated along with the increase of aging, and at 14 weeks of gestation histological examination showed islet *** 12 weeks of gestation, nestin-positive cells could be seen in the pancreatic *** early embryogenesis, islet cells of pancreatic ducts co-expressed insulin, glucagon, and *** pancreatic regeneration after damage, nestin expression of islet cells *** In the early stage of embryogenesis, islet cells of primary pancreatic ducts can be differentiated to multipotential endocrine cells before *** tissue regeneration, pancreatic stem cells may differentiate and proliferate to form pancreatic islet.

关键词： β-cells islet formation differentiation diabetic model regeneration stem cells

Differential bonding behaviors of sodium/potassium-ion storage in sawdust waste carbon derivatives

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Chinese Chemical Letters 2024年第4期35卷 496-501页

作者： Jun-ming Cao kai-yang Zhang Jia-Lin yang Zhen-Yi Gu Xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.

关键词： Porous carbon Sodium-ion storage Potassium-ion storage Bonding behaviors Batteries

Microstructure recognition of steels by machine learning based on visual attention mechanism

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Journal of Iron and Steel Research International 2024年第4期31卷 909-923页

作者： Xing-yu Chen Lin Cheng Cheng-yang Hu Yu-peng Zhang kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)Metallic Composite Materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the *** representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction *** is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure *** reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

Photocatalytic in situ H_(2)O_(2) production and activation for enhanced ciprofloxacin degradation over CeO_(2)-Co_(3)O_(4)/g-C_(3)N_(4):key role of CeO_(2)

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Rare Metals 2024年第6期43卷 2695-2707页

作者： Hong-Jie Zhu Yi-kai yang ming-Hui Li Lu-Ning Zou Hai-Tao Zhao Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical Engin College of Ecology and Environment Anhui Normal UniversityWuhu241002China Liaocheng YiLu Advanced Materials Co. LtdLiaocheng 252000China

The abused ciprofloxacin antibiotics have caused significant environmental *** oxidative degradation of ciprofloxacin exhibits promising efficacy,it often entails excessive energy ***,it is necessary to explore an effective and ecologically sustainable degradation ***,we demonstrated that g-C_(3)N_(4) decorated with the coordinated CeO_(2)and Co_(3)O_(4)(CeO_(2)-Co_(3)O_(4)/CN)exhibited effective ciprofloxacin photodegradation via in situ H_(2)O_(2) production and activation *** indicate that the introduced CeO_(2) enhances the transference of photogenerated electrons to O_(2) by adjusting the oxygen vacancy of photocatalyst,thereby increasing the generation of superoxide radicals,which in turn generate H_(2)O_(2),resulting in a 22.4-fold increase in H_(2)O_(2) generation over g-C_(3)N_(4).Moreover,the in situ H_(2)O_(2)generation facilitated by CeO_(2) is confirmed to be essential for ciprofloxacin degradation via CeO_(2)-Co_(3)O_(4)/CN,as it provides enough oxidant for Co_(3)O_(4) to activate into hydroxyl radicals for the pollutants ***,CeO_(2)-Co_(3)O_(4)/CN achieves a ciprofloxacin degradation ratio of 97.7%within 80 *** study introduces a novel approach that combines H_(2)O_(2) generation and activation,offering an innovative perspective for achieving clean and efficient purification of antibiotic-contaminated water.

关键词： CeO_(2) In situ H_(2)O_(2)generation Ciprofloxacin degradation Photocatalyst

Production induced fracture closure of deep shale gas well under thermo-hydro-mechanical conditions

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Petroleum Science 2024年第3期21卷 1796-1813页

作者： Shi-ming Wei yang Xia Yan Jin Xu-yang Guo Jing-Yu Zi kai-Xuan Qiu Si-Yuan Chen College of Science China University of Petroleum(Beijing)Beijing102249China CNOOC Research Institute Ltd Beijing100028China The University of Hong Kong Hong Kong999077China

Deep shale gas reservoirs have geological characteristics of high temperature,high pressure,high stress,and inferior ability to pass through *** multi-stage fractured horizontal well is the key to exploiting the deep shale gas ***,during the production process,the effectiveness of the hydraulic fracture network decreases with the closure of fractures,which accelerates the decline of shale gas *** this paper,we addressed the problems of unclear fracture closure mechanisms and low accuracy of shale gas production prediction during deep shale gas *** we established the fluid—solid—heat coupled model coupling the deformation and fluid flow among the fracture surface,proppant and the shale *** the fluid—solid—heat coupled model was applied to the fracture network,it was well solved by our numerical method named discontinuous discrete fracture *** with the conventional discrete fracture method,the discontinuous discrete fracture method can describe the three-dimensional morphology of the fracture while considering the effect of the change of fracture surface permeation coefficient on the coupled fracture—matrix flow and describing the displacement discontinuity across the *** simulations revealed that the degree of fracture closure increases as the production time proceeds,and the degree of closure of the secondary fractures is higher than that of the primary *** creep and proppant embedment both increase the degree of fracture *** reduction in fracture surface permeability due to proppant embedment reduces the rate of fluid transfer between matrix and fracture,which has often been overlooked in the ***,it significantly impacts shale gas production,with calculations showing a 24.7%cumulative three-year yield *** study is helpful to understand the mechanism of hydraulic fracture ***,it provides the theoretical guidance for maintaining the long

关键词： Shalegas Fracture closure Fluid-solid-heat coupling Discontinuous discrete fracture

Wnt/β-catenin signaling pathway is active in pancreatic development of rat embryo

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World Journal of Gastroenterology 2006年第16期12卷 2615-2619页

作者： Qi-ming Wang Ye Zhang kai-ming yang Hong-Ying Zhou Hui-Jun yang Department of Anatomy School of Preclinical and Forensic Medicine Sichuan University Chengdu 610041 China Beida Weixin Biology and Science Company Beijing 100081 China

AIM： To elucidate the role of Wnt/β-catenin signaling pathway in pancreatic development of rat embryo. METHODS： The mRNAs of β-catenin, APC, cyclin D1 genes were amplified by means of semiquantitative reverse transcription polymerase chain reaction （RTPCR） from embryonic pancreas in different periods and normal pancreas of rat, respectively. Protein expression of these genes in embryonic pancreas of E14.5-E18.5 was examined by immunohistochemical method. RESULTS： In embryonic pancreas of E14.5, the transcript amplification of β-catenin and cyclinD1 genes was detected. In embryonic pancreas of E18.5, the transcription levels of β-catenin and cyclinD1 genes became much higher than in other periods. But in adult rat pancreas the transcription of cyclinD1 gene could not be observed. Only until E18.5, the transcript amplification of mRNA of APC gene could be detected. Surprisingly, the transcription level of APC gene became much higher in adult rat pancreas than in embryonic pancreas. By means of immunohistochemical staining, identical results were obtained to the above by RP-PCR, except for β-catenin protein in adult rat pancreas. CONCLUSION： Active Wnt/β-catenin signaling occurs in rat embryonic pancreas and is probably important for pancreatic development and organ formation.

关键词： Wnt/β-catenin signaling Pancreas Development Embryo

Hematuria after nocturnal exercise of a man: A case report

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World Journal of Clinical Cases 2024年第5期12卷 1025-1028页

作者： ming-Jian Bai Song-Tao yang Xue-kai Liu Department of Clinical Laboratory Aerospace Center HospitalBeijing 100049China Department of Nephrology Aerospace Center HospitalBeijing 100049China

BACKGROUND A man experienced multiple episodes of macroscopic hematuria following nocturnal *** stones and tumors were considered the two most likely *** patient had two hobbies:Consuming health care products in large quantities and engaging in late-night *** SUMMARY Health care products contain a large amount of calcium phosphate,and we hypothesize that this could induce the formation of small phosphate *** exercise,the urinary system is abraded,resulting in *** patient was advised to stop using the health care ***,the aforementioned symptoms disappeared ***,the patient resumed the above two habits one year later;correspondingly,the macroscopic hematuria *** This finding further confirmed the above inference and allowed for a new avenue to determine the cause of the patient’s hematuria.

关键词： Hematuria Health care products Exercise Case report

Highly Integrated Perovskite Solar Cells-Based Photorechargeable System with Excellent Photoelectric Conversion and Energy Storage Ability

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Energy & Environmental Materials 2024年第5期7卷 336-344页

作者： Jinxin Bi Shaoyin Li Dongtao Liu Bowei Li kai yang ming Xu Chaopeng Fu Yunlong Zhao Wei Zhang Advanced Technology Institute University of Surrey School of Materials Science and Engineering Shanghai Jiao Tong University Dyson School of Design Engineering Imperial College London National Physical Laboratory

Perovskite solar cells have emerged as a promising technology for renewable energy generation. However, the successful integration of perovskite solar cells with energy storage devices to establish high-efficiency and long-term stable photorechargeable systems remains a persistent challenge. Issues such as electrical mismatch and restricted integration levels contribute to elevated internal resistance, leading to suboptimal overall efficiency (ηoverall) within photorechargeable systems. Additionally, the compatibility of perovskite solar cells with electrolytes from energy storage devices poses another significant concern regarding their stability. To address these limitations, we demonstrate a highly integrated photorechargeable system that combines perovskite solar cells with a solid-state zinc-ion hybrid capacitor using a streamlined process. Our study employs a novel ultraviolet-cured ionogel electrolyte to prevent moisture-induced degradation of the perovskite layer in integrated photorechargeable system, enabling perovskite solar cells to achieve maximum power conversion efficiencies and facilitating the monolithic design of the system with minimal energy loss. By precisely matching voltages between the two modules and leveraging the superior energy storage efficiency, our integrated photorechargeable system achieves a remarkable ηoverallof 10.01%while maintaining excellent cycling stability.

关键词： ionogel electrolyte perovskite solar cells photorechargeable system self-powered electronics zinc-ion hybrid capacitor